Running out of patience on my depressed "friend" due to trust issue but I don't want to give up on him.

Like the title says, I'm (22F) running out of patience for my depressed "friend". Our situation is complicated, we like each other, but we can't be together because he explained to me that he's too much to handle (a long list of mental disorders) and that I will hate him and leave him in the long run if we were dating. He's struggling with depression and his text is getting shorter and drier. If it took him 15 minutes to answer my text before but now it takes him half a day or even a day. And he has stopped initiating the conversations. I'm always the one who texts first, makes plan and checks up on him. My sixth sense told me that he had someone else but he denied, saying that he became dry and distant because he didn't want to dump his depression on me. Which I kind of understand because I did push everyone away during my depressed stages. I was anxious and irritated by everyone, my friends knew about my depression and they did the best they could to drag me out, by making me to follow through the plans, taking me out for a drive etc. I'm trying so hard to do the same thing to him. But I feel like I'm talking to a wall. My patience on top of trust issues is running low and I almost texted him today saying that we should stop talking for good. And I think I said "you'll never find the person that you're looking for" somewhere along the lines when I texted him a couple days ago. But now I feel bad about it. If he was just a normal friend then I would probably be more supportive than being jealous of some potentially non-existing person... What should I do? I don't wanna give up on him but the distance he keeps himself away from me hurts so much 😭